Try to balance UI element sizes on windows builds

Author: nyalldawson

python/core/qgis.sip

@@ -108,6 +108,13 @@ Default threshold between map coordinates and device coordinates for map2pixel s
  Default Z coordinate value for 2.5d geometry
   This value have to be assigned to the Z coordinate for the new 2.5d geometry vertex.
 .. versionadded:: 3.0
+%End
+
+    static const double UI_SCALE_FACTOR;
+%Docstring
+ UI scaling factor. This should be applied to all widget sizes obtained from font metrics,
+ to account for differences in the default font sizes across different platforms.
+.. versionadded:: 3.0
 %End
 
 };

src/core/qgis.cpp

@@ -84,6 +84,12 @@ const double Qgis::SCALE_PRECISION = 0.9999999999;
 
 const double Qgis::DEFAULT_Z_COORDINATE = 0.0;
 
+#ifdef Q_OS_WIN
+const double Qgis::UI_SCALE_FACTOR = 1.5;
+#else
+const double Qgis::UI_SCALE_FACTOR = 1;
+#endif
+
 double qgsPermissiveToDouble( QString string, bool &ok )
 {
   //remove any thousands separators

src/core/qgis.h

@@ -120,6 +120,13 @@ class CORE_EXPORT Qgis
      *  \since QGIS 3.0 */
     static const double DEFAULT_Z_COORDINATE;
 
+    /**
+     * UI scaling factor. This should be applied to all widget sizes obtained from font metrics,
+     * to account for differences in the default font sizes across different platforms.
+     *  \since QGIS 3.0
+    */
+    static const double UI_SCALE_FACTOR;
+
 };
 
 // hack to workaround warnings when casting void pointers

src/gui/qgscolorswatchgrid.cpp

@@ -38,14 +38,14 @@ QgsColorSwatchGrid::QgsColorSwatchGrid( QgsColorScheme *scheme, const QString &c
   setFocusPolicy( Qt::StrongFocus );
   setSizePolicy( QSizePolicy::Fixed, QSizePolicy::Fixed );
 
-  mLabelHeight = fontMetrics().height();
-  mLabelMargin = fontMetrics().width( QStringLiteral( "." ) );
+  mLabelHeight = Qgis::UI_SCALE_FACTOR * fontMetrics().height();
+  mLabelMargin = Qgis::UI_SCALE_FACTOR * fontMetrics().width( QStringLiteral( "." ) );
 
-  mSwatchSize = fontMetrics().width( QStringLiteral( "X" ) ) * 1.75;
-  mSwatchOutlineSize = qMax( mLabelMargin * 0.4, 1.0 );
+  mSwatchSize = Qgis::UI_SCALE_FACTOR * fontMetrics().width( QStringLiteral( "X" ) ) * 1.75;
+  mSwatchOutlineSize = qMax( fontMetrics().width( QStringLiteral( "." ) ) * 0.4, 1.0 );
 
   mSwatchSpacing = mSwatchSize * 0.3;
-  mSwatchMargin = mLabelMargin * 1.5;
+  mSwatchMargin = mLabelMargin;
 
   //calculate widget width
   mWidth = NUMBER_COLORS_PER_ROW * mSwatchSize + ( NUMBER_COLORS_PER_ROW - 1 ) * mSwatchSpacing + mSwatchMargin + mSwatchMargin;

src/gui/qgscolorwidgets.cpp

@@ -397,7 +397,7 @@ QgsColorWheel::~QgsColorWheel()
 
 QSize QgsColorWheel::sizeHint() const
 {
-  int size = fontMetrics().width( QStringLiteral( "XXXXXXXXXXXXXXXXXXXXXX" ) );
+  int size = Qgis::UI_SCALE_FACTOR * fontMetrics().width( QStringLiteral( "XXXXXXXXXXXXXXXXXXXXXX" ) );
   return QSize( size, size );
 }
 
@@ -758,7 +758,7 @@ QgsColorBox::~QgsColorBox()
 
 QSize QgsColorBox::sizeHint() const
 {
-  int size = fontMetrics().width( QStringLiteral( "XXXXXXXXXXXXXXXXXXXXXX" ) );
+  int size = Qgis::UI_SCALE_FACTOR * fontMetrics().width( QStringLiteral( "XXXXXXXXXXXXXXXXXXXXXX" ) );
   return QSize( size, size );
 }
 
@@ -991,12 +991,12 @@ QSize QgsColorRampWidget::sizeHint() const
   if ( mOrientation == QgsColorRampWidget::Horizontal )
   {
     //horizontal
-    return QSize( fontMetrics().width( QStringLiteral( "XXXXXXXXXXXXXXXXXXXXXX" ) ), fontMetrics().height() * 1.3 );
+    return QSize( Qgis::UI_SCALE_FACTOR * fontMetrics().width( QStringLiteral( "XXXXXXXXXXXXXXXXXXXXXX" ) ), Qgis::UI_SCALE_FACTOR * fontMetrics().height() * 1.3 );
   }
   else
   {
     //vertical
-    return QSize( fontMetrics().height() * 1.3, fontMetrics().width( QStringLiteral( "XXXXXXXXXXXXXXXXXXXXXX" ) ) );
+    return QSize( Qgis::UI_SCALE_FACTOR * fontMetrics().height() * 1.3, Qgis::UI_SCALE_FACTOR * fontMetrics().width( QStringLiteral( "XXXXXXXXXXXXXXXXXXXXXX" ) ) );
   }
 }
 
@@ -1598,7 +1598,7 @@ void QgsColorPreviewWidget::paintEvent( QPaintEvent *event )
 
 QSize QgsColorPreviewWidget::sizeHint() const
 {
-  return QSize( fontMetrics().width( QStringLiteral( "XXXXXXXXXXXXXXXXXXXXXX" ) ), fontMetrics().width( QStringLiteral( "XXXXXXXXXXXXXXXXXXXXXX" ) ) * 0.75 );
+  return QSize( Qgis::UI_SCALE_FACTOR *  fontMetrics().width( QStringLiteral( "XXXXXXXXXXXXXXXXXXXXXX" ) ), Qgis::UI_SCALE_FACTOR * fontMetrics().width( QStringLiteral( "XXXXXXXXXXXXXXXXXXXXXX" ) ) * 0.75 );
 }
 
 void QgsColorPreviewWidget::setColor2( const QColor &color )

src/gui/qgsmenuheader.cpp

@@ -25,20 +25,20 @@ QgsMenuHeader::QgsMenuHeader( const QString &text, QWidget *parent )
 {
   int textMinWidth = fontMetrics().width( mText );
   mTextHeight = fontMetrics().height();
-  mLabelMargin = fontMetrics().width( QStringLiteral( "." ) );
+  mLabelMargin = Qgis::UI_SCALE_FACTOR * fontMetrics().width( QStringLiteral( "." ) );
   mMinWidth = 2 * mLabelMargin + textMinWidth;
   setSizePolicy( QSizePolicy::Minimum, QSizePolicy::Fixed );
   updateGeometry();
 }
 
 QSize QgsMenuHeader::minimumSizeHint() const
 {
-  return QSize( mMinWidth, mTextHeight + 0.5 * mLabelMargin );
+  return QSize( mMinWidth, mTextHeight + mLabelMargin );
 }
 
 QSize QgsMenuHeader::sizeHint() const
 {
-  return QSize( mMinWidth, mTextHeight + 0.5 * mLabelMargin );
+  return QSize( mMinWidth, mTextHeight + mLabelMargin );
 }
 
 void QgsMenuHeader::paintEvent( QPaintEvent * )
@@ -51,12 +51,11 @@ void QgsMenuHeader::paintEvent( QPaintEvent * )
   //draw header background
   painter.setBrush( headerBgColor );
   painter.setPen( Qt::NoPen );
-  painter.drawRect( QRect( 0, 0, width(), mTextHeight + 0.5 * mLabelMargin ) );
+  painter.drawRect( QRect( 0, 0, width(), mTextHeight + mLabelMargin ) );
 
   //draw header text
   painter.setPen( headerTextColor );
-  painter.drawText( QRect( mLabelMargin, 0.25 * mLabelMargin, width() - 2 * mLabelMargin, mTextHeight ),
-                    Qt::AlignLeft | Qt::AlignVCenter, mText );
+  painter.drawText( QPoint( mLabelMargin, 0.25 * mLabelMargin + mTextHeight ), mText );
   painter.end();
 }